1. Field of the Invention
This invention is directed to unsaturated ester-mercaptothiadiazole adducts and to lubricant compositions of improved friction reducing and corrosion-inhibiting characteristics containing same.
2. Discussion of Prior Art
In view of today's energy crisis there is a continual need for more and better means of reducing energy requirements. The use of additives to reduce or modify friction in internal combustion engines as a means of reducing such engines' fuel requirements is well known. However, the performance of prior art additives has not always lived up to their promise.
It is known from U.S. Pat. No. 2,760,933 to produce a mercaptothiadiazole ester by the reaction of the mercapto function of 2,5-dimercapto-1,3,4-thiadiazole with an acyl compound. It is also known that unsaturated organic acids, such as oleic acid, can be reacted with mercaptothiazoles [by addition of the HS function accross the double bond(s)], see U.S. Pat. No. 4,193,882. Also, U.S. Pat. No. 2,836,564 teaches addition of an alpha-halogenated aliphatic monocarboxylic acid to the mercapto function. Other reactions of general interest involving mercaptothiazoles may be found in U.S. Pat. Nos. 3,776,919, 3,980,573 and 4,136,043 and German Pat. No. 28,560, dated Oct. 20, 1955. However, the adducts of this invention, to the best of applicants' knowledge, were not previously known nor were lubricant compositions containing same known.